The next time you’re scheduled for a Pap test with your primary care physician, you may want to ask why. A survey of more than 1,200 American primary care doctors found that only 22% gave Pap tests consistent with official recommendations: The problem was doctors overused this important diagnostic tool, according to a report published recently in the Annals of Internal Medicine.

To be fair to our hard-working family doctors, Pap guidelines were changed just a few years ago after many years of established testing practices. Shifting testing guidelines for a variety of conditions pose a challenge for physicians to keep up with the latest recommendations. For Pap tests, the guidelines reduced the recommended frequency of testing for certain groups of women. Now the challenge is to reliably incorporate the new guidelines into practice and then confirm their benefit.

The American Cancer Society (ACS) and the American College of Obstetrics and Gynecology (ACOG) recommend that women begin Pap testing at age 21 or within three years of first intercourse, whichever comes first. Annual Pap screening should then continue until age 30, at which time the testing frequency can be cut back to every 2-3 years following three consecutive years of normal Pap tests.

The exception is certain high-risk groups who may need more frequent testing, including women with HIV infection, a weak immune system, in utero DES exposure, or a previous diagnosis of cervical cancer. An abnormal result typically requires a repeat test and potentially further studies, including biopsy.

Women 65-70 years of age who have had at least three normal Pap tests and no abnormal Pap tests in the last 10 years may decide, upon consultation with their doctor, to stop cervical cancer screening. Women can also be considered for cessation of Pap screening if they’ve had a total hysterectomy for a non-cancerous condition or have serious illness that limits their life expectancy.

In the study, four clinical scenarios involving indications for Pap testing were posed to various groups of physicians. Overall, internists performed the best, adhering to guidelines 27% of the time. Family and general practitioners were next at 21%, and obstetrician/gynecologists were only 16% consistent with guidelines. Doctors who performed consistently better were those younger than 40, board certified in their field, and part of large, multi-specialty group practices.

The reason for the over-testing wasn't established. Force of habit may explain some of the variation, but defensive medicine may account for higher testing frequency. For example, the guidelines rely on the patient to report their sexual history. An active sex life with more than one partner places a woman at higher risk of contracting HPV, a known cause of cervical cancer. We know from previous studies that not all patients are forthcoming about their sexual activity, and doctors are well aware of the potential for these omissions. Therefore, some physicians may feel it’s safer to test and not overlook a potential life-saving testing outcome.